The two Chechen brothers accused in the Boston Marathon bombing set about building American lives after coming to the U.S. about a decade ago.

Tamerlan Tsarnaev, 26 years old, became a successful Golden Gloves boxer. His younger brother, Dzhokhar, 19, was a nursing student and became an American citizen just last year, on Sept. 11.

But a close examination of the Tsarnaev family's life in the U.S. shows a hopeful immigrant trajectory veering off course.

For nearly 24 hours, a dragnet of cinematic proportion played out in Boston's eerily quiet streets after the two brothers were branded as the architects of Monday's Boston Marathon bombings. A gunbattle in Watertown, Mass., left Tamerlan dead by early Friday morning, and police put Boston on lockdown after Dzhokhar eluded capture. Later Friday, however, he was apprehended.

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On Friday, details from their lives emerged through interviews with neighbors and relatives, and from their online activities. Acquaintances recalled the brothers as strong students and avid athletes. They left few clues suggesting they would be capable of the gruesome acts the police say they committed.

But the patriarch of the family, a talented auto mechanic named Anzor Tsarnaev, struggled to make a living. Tamerlan, his eldest son, failed to make a career out of boxing, dropped out of community college for lack of money and struggled to find work.

Living on public assistance in a multifamily house in Cambridge, the family began to fray, friends said. The parents separated. Anzor Tsarnaev returned to Russia, battling illness.

Along the way, Tamerlan's attitude seemed to sour. "I like the USA," he told the Lowell Sun newspaper in 2004 while competing in a boxing tournament shortly after arriving in the U.S. "America has a lot of jobs." But a caption accompanying an online photo of him a few years later reads: "Originally from Chechnya, but living in the U.S. since five years…I don't have a single American friend, I don't understand them."

Ruslan Tsarni, an uncle of the two brothers, told reporters outside his Maryland home Friday that his nephews were "losers" who were unable to settle into American life "and thereby just hating everyone who did." He said he didn't think there was an ideological motive. "This has nothing to do with Chechnya," he said. He also indicated there was a rift between him and his brothers. "It's personal," he said, "I didn't like them."

ENLARGE

Tamerlan Tsarnaev, at right in photo, in a 2009 Golden Gloves boxing match in Salt Lake City.
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The boys' mother said in a television interview with the Russian state-run news channel RT Friday night that anyone calling her son a loser is a loser himself. "I am really sure, like I am 100% sure, that this is a setup," Zubeidat K. Tsarnaev said. She also said that she had been contacted by the FBI about her older son, before Monday's deadly attack, as he grew more religious.

The boys' father, in an interview with The Wall Street Journal, said he was present when the FBI interviewed Tamerlan in Cambridge. He said they visited for what they called "prevention" activities. "They said: We know what sites you are on, we know where you are calling, we know everything about you. Everything," Mr. Tsarnaev said.

Another relative—Maret Tsarnaev, the paternal aunt of the brothers—defended the sons. "Nothing points out that my nephews did [the bombings]…I demand evidence," she said.

Photos: FBI Releases

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This photo released Friday by the FBI shows a suspect that officials identified as Mr. Tsarnaev. Federal Bureau of Investigation/Associated Press

The Tsarnaev family, which included two boys and two girls, had come to America after facing discrimination as ethnic Chechens living in Kyrgyzstan during wars in their ethnic homeland. A separatist rebellion there, with elements of radical Islam, had been crushed by the Kremlin under presidents Boris Yeltsin and Vladimir Putin.

Before arriving in the U.S., the family lived in a number of places. Anzor, the father, grew up as an ethnic Chechen in Kyrgyzstan, and said he briefly returned to Chechnya with the family in the early 1990s before moving back to the Central Asian republic. He then left Kyrgyzstan again, facing discrimination. The family lived for a few years in Makhachkala, the capital of Dagestan, where Ms. Tsarnaev's family is from, before moving to the U.S.

U.S. law-enforcement officials said the two brothers came to the U.S. at different times. Dzhokhar arrived with his parents in 2002, just before he turned 10. Tamerlan arrived on his own around 2004. The family was granted legal permanent residence in the U.S. in March 2007, a law-enforcement official said.

An aunt, who already lived in the U.S., helped them get established. Soon they moved into a house in a poorer neighborhood near the border of Boston's Cambridge and Somerville suburbs. There they faced headwinds that many immigrant families encounter.

Terror in the U.S.

One problem was money. The father was unable to find steady work as a mechanic. He struggled to make ends meet by fixing cars on the street for $10 an hour, a practice that prompted neighbors to complain, according to one of the neighbors.

Tamerlan excelled in school but dropped out of Bunker Hill Community College because of money, according to the family's landlord, Joanna Herlihy. In an interview published in a Russian newspaper Friday, the father also recounted his younger son's problems with money, which he said he tried to solve by working as a lifeguard between studies.

Ms. Herlihy, who speaks Russian and helped tutor the children, said Tamerlan's boxing dreams eventually crumbled. "His back was in really bad shape and he couldn't get into the Olympics, and that was the last thing he really worked hard at," Ms. Herlihy said.

Dzhokhar excelled as a student at Cambridge Rindge & Latin School. "I know this kid to be compassionate. I know this kid to be forthcoming," said Larry Aaronson, a retired history teacher at the high school. "Every conversation I had with him—he was generous, compassionate and thoughtful."

A former classmate there said, "His brother and family weren't really Westernized, but Dzhokhar was really integrated into our school community. He was a normal American kid."

Attorney Andrea Kramer said Friday her sons played on the varsity soccer team while Dzhokhar played on the junior-varsity squad. Dzhokhar "wasn't 'them.' He was 'us,'" Ms. Kramer said. "He was Cambridge" and part of a community whose "strength and beauty" is its diversity.

The younger Mr. Tsarnaev was seen on campus at the University of Massachusetts Dartmouth, where he was studying nursing, in the days after the marathon attack, possibly on Wednesday, according to one student who lived in his dorm. He said his roommate shouted "Yo, Dzhokhar" to him in greeting.

Authorities are now trying to determine whether or not the young men had contact with terrorist figures. Last year Tamerlan traveled to Makhachkala, the capital of Dagestan, the Russian republic next to Chechnya where his father currently lives and where he has other relatives as well. Dagestan is home to a simmering Islamist insurgency.

Tamerlan came up with money for the trip and unexpectedly left for the Russian region. A law-enforcement official confirmed that Tamerlan flew out of New York on Jan. 12, 2012, for Moscow's Sheremetyevo Airport and returned July 17. To travel to Dagestan from the U.S., most passengers go through Moscow.

The brothers' father, Anzor, said Tamerlan was with him while in Dagestan. "He wasn't occupied with anything. He was just visiting relatives," Mr. Tsarnaev said. He said there is no way his son interacted with Islamic fundamentalists while on the trip. "There aren't even any of those here anymore," he said.

FBI Releases Photos of Suspects

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Evan Perez and former FBI special agent in charge Andrew Arena, discuss the significance of the Boston Marathon suspects being from Chechnya, Russia. Photo: AP.

Before his departure, Tamerlan was showing signs of stricter religious beliefs, a family friend said. "He started to pray," his father said. About 3½ years ago he had married an American woman who mothered his child and converted to Islam. She was supporting him in recent months as a home health aide, the friend said.

His father said Tamerlan had a domestic incident in his past with his first girlfriend, and had struck her.

Richard Medeiros, who lives in the house behind the suspects, says that six months or so ago, Tamerlan, after being clean-shaven, grew a beard. "He looked like one of those Amish people," said Mr. Medeiros, who is 40 and lives in an apartment building that was evacuated by police and remained cordoned off Friday afternoon. "It made him look really old."

He said he must have shaved it only recently. "That's why I did not recognize him in the photos," he said.

He said his wife wore a black head-covering "down to her eyebrows" and was the friendliest of the group. "She was always asking, 'Hey, how ya doing? Is your leg getting better?'" said Mr. Medeiros, who is on crutches.

Tamerlan also influenced his younger brother. In an interview Friday with a Russian newspaper, his father, Anzor, said Dzhokhar "wouldn't have gotten involved in this against the will of his brother, Tamerlan, and his older brother never would have allowed such things." He denied that his sons were guilty.

In another interview, with a Russian tabloid-news website, he expressed concern about the fate of his sons. "We wanted some peace and calm in life," he said. "And you see what they've found. They were running away from one thing and they met another."

—Lisa Fleisher in West New York, N.J., Sara Germano in New York and David George-Cosh in Toronto contributed to this article.

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